Artificial arm and hand



0. LE G. DILWORTH.

ARTIFICIAL ARM AND HAND.

APPLICATION FILED MAR. 23. 1911.

Patented July 26, 1921.

3 SHEETS-SHEET I- ATTORNEY.-

Patented ul 26,1921.

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0. LE G. DILWORTH,

ARTIFICIAL ABM AND HAND. APPLICATION FILED MAR. 23. 1917.

1,385,81 7. Patented July 26, 1921.

3 SHEETS-SHEET 3.

IN VENTOR.

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A TTORNE Y.

OTTO LE GRAND DILVIORTH, OF HAR'JTFORID, CONNECTICUT. V

ARTIFICIAL Ania AND HAND;

53pecification of Letters Patent. Patented July Application filcdMarch 23, 1917. Serial No. 15?,032.

To all whom it may come m:

Be it known that l, ()rro LE GRAND DIL- woirrir, a citizen of the United States, residing at Harttordfin the county of Hartford and State 01 Connecticut, have invented a new and Improved. Artificial Arm and Hand, of which the following is a specilication.

My invention relates to the class of devices above named and an object oi. my invention, among others, is to provide an artificial arm and hand that may be readily (nierated and that shall have a maximum number of the movements oi": a natural hand and arm, and which movements shall closely imitate those of natural members.

(inc form of device embodying my invention and in the construction and use oi which the objects herein set out, as well'as others, may be attained, is illustrated in the accompanying drawings, in which:

. Figure l is a picture of a man sl'iowing 'my improved artificial arm and hand attached to a stump of his natural inemher.

Fig. 2 is a view oi my improved. hand and arm looking at the outer side.

F S is a similar view looking the upper arm inner side of the arm and hand.

Fi 4 is a view scale enlarged. or up im proved band. and arm with parts broken away to show construction, the forearm being bent upwardly and the hand being turned to a different position from that shown in Figs. 1 to 8.

Fig. 5 is a view similar to F 4, but looking. however, toward the back of the hand.

F 6 vis a detail view, scale enlargedv of the finger mechanism with parts broken away to show construction.

Fig. 7 a detail view through the parts shown in Fig. 6 on a plane denoted by dotted line 77 of Fig. 6.

8 is a detail View, scale enlarged, illustrating the mechanism For producing the wrist movement.

Fig. 9 is a view, looking from the ri ht, of the parts shown in Fig. 8, the cover within the socket being removed.

In the accompanying drawings the numeral 1O denotes avest to be worn by a person. and which closely fits the body and affords a means for anchorage of different parts employed in manipul ting my i or proved hand and arm. These members are attached to the vest in a manner to be hereinaiter described. i

The numeral 11 indicates the upper arm and 12 the forearm of my improved device, the former being hollow, thus providing a recess to receive the stump 13 otthe natural arm. A saddle l4 rests. on theshoulder of the person and has straps l5, 16 attached to the saddle and the upper arm and to the saddle and the vest, as shown in'Figi 1 of the drawings, there being a pair of these at the back arranged and secured in a manner similar to those shown in said figure at the front ofthe person. The saddle may also be secured to the vest, if desired, over the shoulder.

The fore andupper arms may be constructed. of any suitable, light material, common to structures of this class and the "forearm is preferably hollow from end toend,

lower end of the upper'arm 11' projects into the end of the forearm'and these; two members are pivotally united as by a pivot 18 secured in the jectin beyond entering supporting straps 19 and 48 secured to opposite sides of the forearm and projecting beyond its, upper end, said straps having a swinging movement on said pivot.

The forearm is balanced, so that it may be moved into the position shown in Fig; t, by the application of little force, In the structure shown herein an abutment '20 extending across the opening in the forearm receives the threadeddstem otan adjustingscrew 110, the millededge of the head oi. which extends through an opening at the back of the forearm. This has a recess 21 to receive the. end of a spring case 22, which member 11 with its ends prothe SIClGS Of said member and and it is cut away on one side as ati'? The end is of curved form so that said case may 1;

have a rocking movement. A spring 23., preferably of spiral form is seated in this spring case, the latter being open at its upper end, said spring thrusting with its upper end against a shoulder 2e on a plunger 25 that extends into the upper end of the case 22. A stud 26 atfthe upper end of the plunger 25 projects into a sleeve 27, said sleeve being thus supportedby the plunger.

A ball 28 on the end of a strut rod-29 is 1 thus tendsto bend the arm into the position 33 that is a bell crank Fig. 1 of the drawings.

stump 13, either straight posite end of said va strut rod 34 with a projection from the .upperend of the .2 of the drawings. '32 is provided pressed against shown in Fig.4.

Two ways of bendingthe arm into the position shown in Fig. 4 are contemplated by me, and eitherone may beused under V certain conditions.

" 'fecting this bending operation comprises a One mechanism for efbending cord 30 secured inside of the forearm at the wardly through the cut-away part 17, into the front of the lower end of the upper arm, through this end of the upper arm and out through *the back thereof where it is attached to an anchoring strap 31 extending to the front of the vest 10 as shown in a movement of the down or forward, will .cause the cord 30 to pull upon the forearm and swing'it into the position shown in Fig.4.

As another means of bending the arm I this arrangement provide a spring actuating member 32 secured to the front of the upper arm as shown in Fig. 1, and passing around said arm to the opposite side thereof where it is pivotally attached to an arm bending lever lever pivotally mounted on the'outside ofthe upper arm, the op lever being connected by strap 19 as shown in Fig. The actuating member witha pad 35 adapted to be the side of the body under-- neath the arm and as illustrated in Fig. 1.

It will be seenfrom this construction that by pressing the arm stump against the side of the person the upper end of the lever will be pressed forward and its opposite end downwardly, and, acting .upon the projection from the strap 19, the forearm will be swung upwardly to the position shown in Fig. 4, the balance of this arm, as hereinbefore described, enabling this action to be P readily effected. This means of bending the arm maybe employed in instances where the upper 50 arm member is located againstthe side of the person but when saidupper arm member may be raisedthen the other means hereinbefore described may be employed to effect bending action of the arm, as to cause the hand to reach the head.

The opening in the lower end of the forearm 12 is closed by a socket piece 36 that ing a bearing in opens to the interior ofthe arm, piece being secured in place in any desired manner. A shaft 37, preferably hollow. is mounted in the socket piece and projects be yond thelo wer end thereof andout ofthc forearm, the opposite endof the shaft havacover 38 secured within the socket piece and. closing one end thereof. A coupling collar 39 is rotatably and slidback thereof and extending up-' over the shoulder and preferably secured of the pawl and arm ing adapted to engage this socket.

the forkedarms of a coupling lever 40, the 7 end of saidalever opposite its fork projecting through the side of the socket piece. This lever is pivotally mountedin the socket piece, as shown in Fig. 5 of the drawings, and its outer end lies in the path of movement of wrist movement controlling teeth 41 of a ratchet wheel 42 loosely mounted on a stud 43 secured to and projecting from the side of the socket piece and through a hole in the lower end of the forearm. A coupling arm 44 is also pivotally supported on the stud 43, and carries a pawl 45, a coupling cord 46 being secured to said arm. This cord passes upwardly in contact with a guide sheave 47 rotatably mounted on'that end of the pivot 18 that receives a support ing strap 48 secured to the forearm 12 on the opposite side from the strap 19 and serving a purpose similar to that of the strap 19. Above the sheave 47 the cord 46 passes through a suitable guide at the upper end of the upper arm'll and on the side thereof toward the body, said cord passing under the actuating member 32. and being secured to an'anchoring strap 49 secured to the vest 10 and extending preferably across the front of the vest and over the opposite shoulder from that supporting the arm, said strap being preferably secured just behind said .lever on the application of suflicient force applied to rotate the ratchet wheel. The ratchet teeth 51 on the ratchet wheel are-so spaced with relation to the wrist movement controlling teeth that little lost movement 44 will take place in the swinging movement of the arm to cause step by step movement of the ratchet wheel. .A coupler 52 is pivotally mounted in the upper end of the shaft 37, its outer cndbelocking notches 53 in a locking ring 54 secured of the socket piece These locking notches are located to hold the hand in different positions into which it may be turned in its pivotal movement at the wrist. The core pling collar 39 has a coupling notch 55 in its upper edge adapted to receive said cou pler.

An actuator for turning the hand, in the form herein shown consisting of acord 56, has its ends secured in a groove in thecollar 39, the branches of this cord extending out through eyes 57 in the lower arm section, (see Fig. 2) the loop of this cord extending around a guide sheave 58 rotatably mounted on the lower arm member. The

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to the'inner wall coupling arm 44 is held in a normal position of rest by means of an arm returning spring 59 secured to an extension from the arm 44011 the opposite-side of its pivot from that at which the cord 46 is attached. A hand turning bar 60 issecured to one of the branches of the loop of theactuator 56, and, as shown in Fig. 2 of the drawings, the outerend of this bar is rigidly attached to a hand turning rod (il-pivotally connected at its upper end to a: rod support 62 located at the upper end of the strap 19.

From the above construction it will be noted that when the coupling cord 46 is drawn upon, the arm 44 will be swung on the stud 43 and against the tension ofthe -arm returning spring 59, this movement through the action of the pawl rotating the ratchet wheel 42 and carrying the beveled portions of the wrist movement contro1 ling teeth 4-1 against thecoupling lever d0, swinging it on its pivot and movingits forked end to carry the coupling collar 39 against the coupler 52, moving the latter from locked engagement with the locking ring 54.

This pull upon the cord 4C6 is obtained by raising the shoulder on the opposite side of the body from that to which the artificial arm is attached or by moving the stump of the arm away from the body, and the ratchet wheel being consequently turned, as hereinbefore described, a retaining notch 50 on a controlling toothel will be moved under thelever 40 that will drop into-said notch and thus be held in its unlocking and coupling position. Abending' of the arm, which may beefi'ected as hereinabove described, either by the operation of the bending cord 30 or the actuating member 32, will'cause the bar to be moveddownwardly on the forearm, owing to the location of the pivot ofthe rod 61 upon a difierent center from that on which the forearm turns and a consequent 'opposition'to upward movement of said bar by said rod, and the actuator 56 will operate to turn the collar 39 in the direction indicated by the arrow in Fig.9. This movement will carry the coupling notch 55. in the collar underneath the coupler 52 that will drop into the notch thus locking the parts together, but the coupler will not drop low enough to again engage the locking notches 53, as-the holding of the lever 4L0 by the teeth l1 willretain the coupler above the ring 54. This movement to lock the parts together will take place during the first part of the bendinginovement of the arm, and during the rest of such bending movement the continued rotation of the collar 39 will cause the handto turn as for the purpose. of carrying a spoon held in the fingers to the mouth; If a glass of water he held in the handjthis turning movement should beavoided, and the unlocking-opera- The end of tion above described will not be effected. If it be desired to retain, the hand in the position to which it has been turned asabove described and as illustrated in Figs. 4 and 5, a second upward movement of the shoulderor movement of the stump away; from the body and a consequent pull upon the cord 46' \Vlll force the tooth 41 supportingthe lever 40 from engagement with said lever, and its end will drop into the deep spaces between the teeth, thus placing the lever in its locking and uncoupling position, and as shown inFig. 5 of the drawings.

From the above description it will be seen that the same movement of the body is made use of to effect the locking-and unlocking of the wrist movement.

The wrist mechanism above described includes a wrist piece 63 having a circular shaped recess 64 and projecting bearings 65, the latter to receive a pivot bolt 66 that passes through said bearings, through the shaft 37 and through the base of the hand 67, the bolt being secured as. by means of a nut, as shown in Fig. .5 of the drawings. this hand is formed on the arc of a circle struck from the center of the pivot bolt 66 as is also the recess 64;, and this end of thehand has recesses 68 to receive the projections65. A thumb .69 is pivotally attached to the hand in .anyfsuitable manner, and is forced normally inward as bymeans of a spring. The hand has a recess70 to receive a frame'that' issecured therein in any suitable manner. This frame comprises side parts 71 and a bottom plate 72. Sockets 73 are secured to the side parts and receive plungersw'fet that are seated-on springs 7 5 in the sockets. These plungers are joined by a finger actuating bar 7 6 that is operated by mechanism as-iollows:

A carrier plate 77 is pivotally supported at one end on the bottomrplate 72' and carries-a retaining slide '78 having a retaining finger 79 positioned to engage openings in a locking plate 80 secur-ed to the bottom plate 72. p A retaining stud81 projects from the slide .78 'in position" to engage retaining notches in the holdingteeth 82 of a ratchet wheel 83 rotatably mounted on a stud 84 secured in the carrienplate 77. A lock actuating lever 85 is pivotally mounted on the pin 86 that pivotallysupports the plate 77, and a pawl 87 is pivotally mounted on the lever 85 with its toothed end positioned to engage the teeth of theratchet wheel. The lever'85 has a bar 88 extending underneath the plate 77 and joined to the main partof the plate by a screw 89 to which an actuating cord 90 is secured. :A spring 91 forces the lever 85 in direction opposite to that in which it may be movedby the cord 90, and a spring 92 forces the slide 78toward the locking plate 80 to engage the finger 79 with the openings in said'plate. The

' bar 76 is composed of a number of sections,

' .nected' with the finger three as shown in the drawings herein, and they are united by a rod 93 passing through said fingers and through finger base actuating rods 94. The stud 84 is formed integral with a supporting plate 95 that is extended upwardly and has an overturned lip 96. to receive a supporting ear from a tie bar 97 secured to the actuating bar 76, a screw 98 securing the parts together.

Each of the fingers consists ofa base 99 pivotally attached to the hand and ,a tip 100 pivotally attached to the base. The little finger is supported on a pivot 101, while the first, second and third fingers are'supported on a pivot 102 for the three. An actuating rod 9 1 extends from the bar 7 6 to each of the fingers. Each rod is connected with one end of a finger tip actuating lever 103, the opposite endof said lever being conbase 99. Afinger tip actuating rod 105 pivotally connects each lever 103 with a finger tip 100.

V cord 90 which may after which a continuous The actuating cord .90 extends from the lever 85 through the hand and diagonally out through an opening in the wrist piece 63 to the back of the hand and along the forearm and through a guide 107 on the upper arm and to an anchoring strap 108 secured to the vest 10 preferably on the shoulder.

The fingers are closed'by a pull upon the be effected by lowering the shoulder of the stump to which the arm is attached. The arm will thus be extended away from the anchoring strap 108 and the actuating lever85 will receive the force of this pull. The spring 91 is stronger than the} springs 75, with a result that a pull upon the cord- 90 will swing the carrier plate 77 and cause it to operate the entire. finger mechanism to close the fingers ina manner that will be readily understood. ;As soon as opposition to; closing movement of the fingers takes place, as by an object within the hand, or a closing of the fingers together,

swinging movement of the plate 77 will stop and the spring 91 will then give to permit movement of the actuating lever 85, and the latter, throu'gh'the action of the pawl 87 will rotate the ratchet 83 on its pivot. This arm and aforearm pivotally attached thereoperation, if the slide 78 is in its lockediposition, will, by the action of the cams on the teeth '82, move the slide to itsunlocked position, and if the slide is in its unlocked position, the holding notch inthe tooth 82 will be forced from engagement with the stud on the slide that will then be permitted to move to its locked position under force of the spring 92. It will thus be seen that the fingers may be caused to grasp an object, pull on the cord 90 will cause the fingers to be locked in this position and the hand and arm may then be operated as hereinbefore described. When it is desired to loosen the fingers from the means of a spring unlocked fromthe notch tion.

and extending between said the same manner as unlocking movements take place by, the same action of the cord 90.. i -f The pawl 87 is; held normally in engagement with the teeth of the ratchet wheel by 111 secured'to the pawl and to a screw in the end of the stud 84:. The bar 88 is formed from a portion of the lever 82 bent into proper form,the bent portion forming a stop 109 to limit the movemerit of the lever 85 with, respect to the plate 77.

ment on the pivot 66, by forcing .it into various positions, andthe friction between the parts will be sufficient to retain the hand in any such position to which it may'have been moved.

The hand may its back toward be swung to a position with the front, which will be necessary, for some purposes, and in such case, if the hand is lockedin this position, the coupler 52 will be swung in a direction opposite to that indicated by the arrow in Fig. 9 and to engage the notch at the top of said figure. This result may be attained before, and itthus becomes apparent--that both the, locking and' The hand may be bent, by a move-' by bending vthe arm until the coupler 52 is V 53, the arm being only partially bentto effect this purpose. This movement will carry the coupling notch 55 into locked engagement with the coupler, and now lowering the forearm, the coupling collar will move the shaft .87 and consequently ;the hand in a} reverse direction to that indicated by the arrow in Fig. 9. The

.hand may be locked in this position by opcrating the mechamsm as hereinbefore described, and it may be unlocked and carried to the position shownqin Figs. 1 and 2, and lockedand. unlocked in this position, 'or it may be turned to the position shown in Figs. 4 and 5 andlocked or unlocked in this posi- Thisturning movement is a swivel movement .of'the hand with respect to the forearm that is obtained by means of the turning movement of the. shaft to which the hand is secured. r

I claim 7 l I 1..An artificial limb including an upper of the. wearer for actuation of said member,

and a connection between said actuating member and forearm to effect bending movement of the latter. 1

-2. Anartificial limb including an upper arm and aforearm pivotally attached there- .to, an actuating member partiallyencircling and movably supported by the upper arm arm and the body toreceive-pressure therebetween, and a connection between saidactuating member and forearm to effect bending movement of the latter by reason of such pressure.

3. An artificial limb including an upper arm and a forearm pivotally attached thereto, an actuating member movably secured to the inside of the upper arm to be actuated by pressure against the body, a bending lever pivotally attached to the upper arm, an operative connection between the bending lever and said actuating member, a strap secured to the forearm and projecting above its up per end, and a strut rod pivotally attached to said bending lever and to said projecting strap to effect bending movement of the forearm.

4. An artificial limb including an upper arm and a forearm pivot-ally attached thereto, a hand having a swivel connection to the lower end of the forearm to turn on the longitudinal. axis thereof, an actuator movably mounted on the forearm and operatively connected with the hand to turn it on said longitudinal axis, and a connection between said actuator and the upper arm to effect movement of the actuator as the arm is bent.

5. An artificial limb including an upper arm and a forearm pivotally attached thereto, a hand having a swivel connection to the lower end of the forearm to turn on the longitudinal axis thereof, an actuator movably mounted on the forearm and operatively connected with the hand to turn it on said longitudinal axis, and a connection extending from the actuator and pivotally connected to the upper arm at a point re moved from the axis of the forearm in its turning movement on the upper arm.

6. An artificial limb including an up er arm, a forearm pivotally attached thereto and having an abutment, a spring case seated against said abutment, a spring inclosed in said case to thrust it against said abutment, and a strut rod secured'to the upper arm and connected with the spring to resist expanding movement thereof whereby expansion of the spring assists in bending movement of the forearm.

7. An artificial limb including an upper arm, a forearm pivotally attached thereto, and a spring positioned and arranged to exert thrust between said upper and forearms in a direction to influence bending movement of the latter.

8. An artificial limb including an upper arm, a forearm pivotally attached thereto a strut rod secured to the upper arm, an abutment in the forearm, a spring casing supported by said abutment, a spring within said casing, and a connection between said spring and strut rod whereby said rod reslsts said expanding movement of the spring.

9. An artificial limb including an upper member, a forearm pivotally attached thereto, a handswivelly attached to the forearm to turn on the longitudinal axis thereof, means for locking the hand in differentposit/ions, an actuating member for bending the arm, an actuating member for turning the hand, and an actuating member for the locking mechanism, all extending to.- and connected with the upper arm.

10. An artificial limb including an upper arm, a forearm pivotally attached thereto, a hand swivelly attached to the forearm, fin gers movably attached to the hand, mechanism for locking the hand against movement, actuating members connected one to the finger moving mechanism, and one to the hand locking mechanism and extending and secured to a vest, and a vest adapted to be secured to a person.

11. An artificial limb including an upper arm, a forearm pivotally attached thereto, a hand swivelly attached to the forearm to turn on the longitudinal axis thereof, mechanism for turning the hand, mechanism for locking the hand against movement, fingers movably secured to the hand, mechanism for moving the fingers, and actuating members extending one from the forearm to bend it, one from the hand turning mechanism, one from the hand locking mechanism, and one from thefinger moving mechanism, all of said actuating members being attached to the upper arm.

12. An artificial limb including a forearm, a hand swivelly attached to the forearm to turn on the longitudinal axis thereof, means for locking the hand in different positions, and an actuating member connected with said locking means and movable in the same manner both to lock and unlock the said locking mechanism.

13. An artificial limb including a forearm, a hand swivelly attached to the forearm, a lock to lock the hand in different positions, mechanism for operating the lock and including a member movable in the same direction to lock and unlock the arm, and a cord connected with said member and operating by a pull to cause both locking and unlocking action of said mechanism. 14. An artificial limb including a forearm, a hand swivelly attached to said forearm, a lock to lock the hand in different positions, a member rotatably mounted for step by step movement to move the lock to locking and unlocking. positions, and means for effecting step by step movement of said rotating member.

15. An artificial limb including a forearm, a hand swivelly attached thereto on an axis extending longitudinally of the forearm, mechanism for turning the hand on said axis, mechanism for locking the hand in different positions to which it' may be turned on said axis, means for connecting and disconnecting said locking and turning mechanism, and. 1116 1. 18 for actuating each the coupler forlocking action,

arm,

of said mechanisms to retain the hand in different positions to which it may be turned.

the arm is bent, a locking mechanism, means "to connect said locking mechanism and sand turning mechanism, said lock.

17. An artificial limb including a forea hand swivelly attached thereto, mechanism for locking the hand in different positions, mechanism for turning the hand, means to couple the locking mechanism With the turning mechanism, and a member having'a step by step movement always in one direction to operate said lock for locking and unlocking action, and means for operating said member.

18. An artificial limb including a forearm, a shaft rotatably mounted in said arm, a hand secured to said shaft, means for roand means to operate tating said shaft and including a sliding collar, means for actuating said collar, means including a coupler for locking the hand in different positions, said coupler being located in the path of movement of said collar to be actuated thereby, and means for actuating the collar.

19. An artificial limb including a forearm, a .shaft-rotatably mounted in the forearm, a hand secured to said shaft, a coupler pivotally mounted in the shaft, a collar slit ably mounted on the shaft to actuate said coupler and having means to receive the coupler for coupling action, means engaged by r and means for actuating the collar.

20. An artificial limb including a forearm, ashaft rotatably mounted in said arm, a hand secured to said shaft, a coupler pivotally secured to said shaft, a locking ring having notches to receive said coupler, a sliding collarhavi'ng a notch to receive said coupler, and means for operating'the collar.

21. An artificial limb including a forearm,

ing the shaft with the hand in different pci sitions, means movable on the shaft to operate said lock, and means engaging the lock operating means to effect turning movement of the hand.

22. An artificial limb including a forearm, a shaft rotatably mounted in said arm,

extending around the collar to effect turnarm, a socket shaft, a locking ring the arm, means a shaft rotatably mounted in said arm, a hand secured to said shaft, means for locking movement of the hand, and means for operating the collar. I

23. An artificial limb including a forearn1,a hand sivi'velly attached to said arm, a coupler pivotally mounted and rotatable with said hand, a sliding collar having a notch to receive said coupler, means to operate the collar, and means to engage the coupler to lock the hand against turning movement. V 24:. An artificial limb including a forearm, a shaft rotatably mounted therein, a hand securedto said shaft, a coupler pivotally mounted in the shafflmeans to engage said coupler for locking action thereof, a collar slidz-bly mounted in the shaft to operate said coupler for locking and unlocking action, said collar having a groove to receive said coupler for coupling action, an. actuating cord extending around said collar to effect turning movement thereof, and means for actuating the collar. I

25. An artificial limb including a forepiece secured in the lower end of said arm, a shaft rotatably mounted in said socket piece, a hand secured to said located inside of the socket piece and having notches, a coupler pivotally mounted in the shaft'to engage said locking notches, a collar slidably mounted on said shaft-to OPBIiLfZBSIld coupler and having a notch to be engaged by the coupler for coupling action, a cord extending around said collar to the outside of connected with the cord to effect rotation of said collar, and means for operating the collar for locking'and unlocking action.

26. An artificial limb including a forearm, a hand swivelly mounted on said arm to' turn on an axis extending longitudinally of the arm, means for turning the hand, mechanism for locking the hand in different positions and including a lever, ai'otating member to actuate said lever for locking and unlocking movements, and means for imparting a step by step movement to said rotating member. 1 i

27; An artificial limb including a forearm, a hand swivelly attached thereto, means for turning the hand, mechanism for locking the hand in different positions, and lock operating mechanism including a lever, a toothed member to operate said lever and having notchesat the crowns of the teeth to engage and hold said lever in unlocked po- 'sition, and means for imparting a step by step movement to said toothed member.

28. An artificial limb including a forearm, a hand sivivelly attached thereto, means for turning the hand, mechanism for locking the hand in different positions and including a lever, a member rotatably mounted and having teeth with notches in th crowns to receive and hold said lever in ill.)

unlocked position, a coupling arm mounted for reciprocating movement and opera tively connected with said rotatable member, and means for actuating said arm.

29. An artificial limb including a forearm, a hand swivelly attached thereto, mechanism for turning the hand, mechanism for locking the hand in different positions and including a. lever, a toothed member rotatably mounted and having notches to engage said lever to hold it in unlocked post tion, a ratchet wheel attached to said toothed member, a coupling arm having a pawl to engage said ratchet, and means for operating said coupling arm.

30. An artificial limb including a forearm, a hand swivelly attached thereto, means for turning the hand, mechanism for locking the hand in different positions and including a lever, a toothed member having a set of notches to engage and hold said lever in unlocked and coupled position and also a set of notches to hold said lever in uncoupled and locked position, and means for imparting a step by step movement to said toothed member always in the one direction.

31. A hand having fingers attached thereto for bending movement, a carrier plate connected with the fingers to move them in one direction, springs to return the plate in the opposite direction, an actuating lever pivotally mounted, a spring connection between said plate and lever stiffer than the springs for effecting said returning movement of the fingers, and means for actuating said lever.

32. A hand having fingers attached thereto for bending movement, a frame secured within a recess in the hand, a bar slidably mounted and operatively connected with said fingers, plungers attached to said bar, springs upon which said plungers are seated, a pivotally mounted carrier plate operatively connected with said bar, an actuating lever having a movement independent of said plate, means for connecting the lever with said plate after the lever has effected part of its movement, said connecting means including a spring stiffer than the springs upon which said plungers are seated, and means for operating said lever.

A hand having fingers attached there to for bending movement, and having a recess, a frame located in said recess, a bar slidably mounted in said frame, plungers supporting said bar, springs upon which said plungers are mounted, a carrier plate operativelyconnected with said bar, an actuating lever having a movement independent of said plate, a spring and said plate and stiffer than springs supporting said plungers, means for actuating said lever, means for connecting said lever with the slide after the lever has effected part of its movement, and a locking bolt operatively connected with the actuating member to be operated thereby.

341. An artificial limb including an upper arm, a forearm pivotally attached thereto, an actuating member movably secured to the upper arm and located to receive pressure between said upper arm and the body of the wearer for actuation of said men'iber, a connection between said actuating member and forearm to effect bending movement of the latter, and a second means for effecting bending movement of said forearm.

'35. An artificial limb including a forearm, a hand swiv-elly mounted on said forearm to turn on the longitudinal axis thereof, means for turning the hand in one direetion, mechanism for locking the hand in different positions and including a lever, a 1'0- tating member to actuate said lever for looking and unlocking movements, means for turning the hand in an opposite direction for efiecting unlocking movement, and means for actuating said rotating member.

OTTO LE GRAND DILWOR-TH.

connecting said lever 

